<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <script src="../react18/react.development.js"></script>
    <script src="../react18/react-dom.development.js"></script>
    <script src="../react18/babel.min.js"></script>
  </head>
  <body>
    <button id="btn">改变</button>
    <div id="app">
      <h1>天气预报</h1>
      <p>今日小雨</p>
    </div>
    <script>
      const oApp = document.getElementById("app");
      const oBtn = document.getElementById("btn");

      oBtn.onclick = function () {
        const str = `
        <h1>天气预报</h1>
        <p>今日晴天</p>
        `;

        oApp.innerHTML = str;
      };
    </script>
  </body>
</html>
